We propose to develop SITS, a wearable trunk stabilization neuroprosthesis for use by people with mid-thoracic to low-cervical level spinal cord injury during lifting, pulling, reaching, and wheeling tasks. SITS will stimulate the extensor muscles of the lower back using surface electrodes to stiffen the trunk. We hypothesize that users will be better able to perform tasks and maintain seated posture when the system is active. In Phase I, we will develop a prototype system that will include an input device, electronics, a stimulator, and surface electrodes. We will demonstrate feasibility through a series of experiments in which subjects perform lifting, pulling, reaching, and wheeling tasks, with and without the SITS system. System efficacy will be evaluated using task performance measures and biomechanical measures of postural stability. An electrode garment will be designed to provide repeatable donning of the electrodes without assistance. A focus group of potential users will provide input regarding the electrode garment, device design, and potential uses for the system. In Phase II, we will further develop the electrode garment, combine the components into a single portable package, investigate physiological benefits of system use, and perform an extensive evaluation with a large subject pool. PROPOSED COMMERCIAL APPLICATION: The target price for the proposed device will be $750-$1000. The market will be individuals with mid-thoracic to low-cervical level SCI who have impaired trunk control and would be eligible for using an electrical stimulation system. This population is estimated to be approximately 5,000-10,000 people.